H3D Output

Command ElementDefines an H3D output command.

Example

<H3DOutput
     switch_on          = {"TRUE | FALSE"}
   [ increment          = "integer" ] 
   [ format_option      = {"MODAL | NODAL | AUTO"} ]
   [ stress_option      = {"NONE | TENSOR"} ]
   [ strain_option      = {"NONE | TENSOR"} ]
   [ gpstress_option    = {"NONE | TENSOR"} ] 
   [ start_time         = "real" ]
   [ end_time           = "real" ]
   [ elemforce_1d       = {"TRUE | FALSE"} ]
   [ nodal_velocity     = {"TRUE | FALSE"} ]
   [ nodal_acceleration = {"TRUE | FALSE"} ]
   [ linear_animation   = {"TRUE | FALSE"} ]
/>

Attributes

switch_on
"TRUE" creates H3D file, "FALSE" does not.
increment
Controls how often data is written to the H3D file. For example, "2" means data is written at every second step.
format_option
Select from "MODAL", "NODAL" and "AUTO" (Default = AUTO).
stress_option
Select from "NONE" and "TENSOR" (Default = "TENSOR").
strain_option
Select from "NONE" and "TENSOR" (Default = "TENSOR").
gpstress_option
Select from "NONE" and "TENSOR" (Default = "TENSOR").
start_time
Specifies the start time for writing the H3D. The following conditions must be met:
  • start_time >= 0.0
  • start_time < simulation end time
  • start_time <= end_time
end_time
Specifies the end time for writing the H3D. The following conditions must be met:
  • end_time <= simulation end time
  • start_time <= end_time
elemforce_1d
Select "TRUE" or "FALSE" to enable or disable 1D element force export to the H3D file.
nodal_velocity
Select "TRUE" or "FALSE" to enable or disable nodal velocity output to the H3D file.
nodal_acceleration
Select "TRUE" or "FALSE" to enable or disable nodal acceleration output to the H3D file.
linear_animation
Select "TRUE" or "FALSE" to enable or disable linear analysis mode shapes to be output to the H3D file.

Comments

  1. The H3DOutput command produces an H3D file for animation.
  2. When the model includes flexible bodies, the format_options "MODAL", "NODAL", and "AUTO" provide control over file size.
  3. If format_option = "MODAL", the mode shape data and time history of the modal participation factors are stored in the H3D file. This approach incurs a computational cost during visualization as nodal results must be computed from modal results on the fly.
  4. If format_option = "NODAL", nodal data are stored for each time frame instead. This usually produces larger H3D files than the "MODAL" option, however, it increases the visualization performance.
  5. If format_option = "AUTO", the most efficient option in reducing the H3D size is automatically determined.
  6. If stress_option = "NONE", then element stress results are not output to the H3D file. This option reduces the H3D file size for large models if stress results are of no interest.
  7. If stress_option = "TENSOR", the element stress results are written in tensor format to the H3D file. HyperView calculates the vonMises and other parameters from the stress tensor.
  8. The strain_option and gpstress_option work in the same way as the stress_option.
  9. For the gpstress_option, grid point stresses are written in tensor format to the H3D file.
  10. If the FlexH3D file does not have element stress mode shapes, then the stress_option is ignored.
  11. If the FlexH3D file does not have grid point stress mode shapes, then the gpstress_option is ignored. Grid point stresses must be explicitly requested in OptiStruct during the CMS analysis.
  12. For the attributes nodal_velocity and nodal_acceleration to work properly, flex_vel_acc_output = "TRUE" must be set in the Output: Results command. If it is not, nodal_velocity and nodal_acceleration are not be written to the H3D file.
  13. When linear_animation is set to "TRUE", there has to be a linear analysis in the simulation. The linear analysis generates <results_name>_linz.mrf, which is a requirement for the linear animation output to the H3D file.
  14. The start_time and end_time can be used to reduce the size of the H3D in cases where the H3D generated is very large. You can specify a window of interest where you would like to view the animation and skip the H3D generation for the remaining time in the simulation.